はじめまして!
Hello!
Ciao! :)
I'm a Postdoctoral Researcher at the Kavli Institute for the Physics and Mathematics of the Universe (IPMU), by The University of Tokyo. My main research focus is dark matter in galaxies, which I study with gravitational lensing.
I obtained my PhD at the University of California, Santa Barbara, with the thesis "Luminous and dark matter in early-type galaxies". Before then I lived in beautiful Lucca, Italy, where I was born and raised, and did my studies at Università di Pisa.

Contact Information:


Email address:


Kavli Institute for the Physics and Mathematics of the Universe
The University of Tokyo
5-1-5 Kashiwanoha
Kashiwa, 277-8583
Japan

Curriculum vitae




Research Interests


My main focus is the physics of massive galaxies, which I study using gravitational lensing. As a member of the Hyper Suprime-Cam strong lensing working group, I am currently involved in the Survey of Gravitationally-lensed Objects in HSC Imaging (SuGOHI). The aim of SuGOHI is to collect a large sample of strong lenses, taking advantage of the amazing data produced by HSC, and use them to study the structure of galaxies, galaxy groups and clusters. For this purpose, I developed a strong lens finder, called YattaLens, which helped find tens of previously unknown lenses, such as these.

I am also using weak lensing to obtain accurate halo mass estimates of massive galaxies in HSC. For this study, I am using a new analysis method I developed, based on a Bayesian hierarchical inference approach.

Finally, I am a member of the H0LiCOW collaboration, devoted to the measurement of cosmological parameters with time-delay measurements of strongly lensed quasars.


Selected publications:

Updated 2017-11-6

Sonnenfeld, A.
"On Power-law Density Profiles in Time Delay Cosmography"
2017, submitted to MNRAS, arXiv:1710.05925

Sonnenfeld, A. & Leauthaud, A.;
"A Bayesian Hierarchical Approach to Galaxy-Galaxy Lensing"
2017, submitted to MNRAS, arXiv:1710.00007

Sonnenfeld, A.; Chan, J. J.; Shu, Y.; More, A.; Oguri, M.; et al.
"Survey of Gravitationally-lensed Objects in HSC Imaging (SuGOHI). I. Automatic search for galaxy-scale strong lenses"
2017, Publications of the Japanese Astronomical Society, in press

Sonnenfeld, A.; Nipoti, C.; Treu, T.;
"Merger-driven evolution of the effective stellar initial mass function of massive early-type galaxies"
2016, Monthly Notices of the Royal Astronomical Society, 465, 2397

Sonnenfeld, A.; Treu, T.; Marshall, P. J.; Suyu, S. H.; Gavazzi, R.; Auger, M. W.; Nipoti, C.
"The SL2S Galaxy-scale Lens Sample. V. Dark Matter Halos and Stellar IMF of Massive ETGs out to Redshift 0.8"
2015, The Astrophysical Journal, 800, 94

Sonnenfeld, A.; Nipoti, C.; Treu, T.;
"Purely Dry Mergers do not Explain the Observed Evolution of Massive Early-type Galaxies"
2014, The Astrophysical Journal, 786, 89

Sonnenfeld, A.; Treu, T.; Gavazzi, R.; Suyu, S. H.; Marshall, P. J.; Auger, M. W.; Nipoti, C.
"The SL2S Galaxy-scale Lens Sample. IV. The dependence of the total mass density profile of early-type galaxies on redshift, stellar mass, and size"
2013, The Astrophysical Journal, 777, 98

Sonnenfeld, A.; Gavazzi, R.; Suyu, S. H.; Treu, T.; Marshall, P. J.
"The SL2S Galaxy-scale Lens Sample. III. Lens Models, Surface Photometry and Stellar Masses for the final sample"
2013, The Astrophysical Journal, 777, 97

Sonnenfeld, A.; Treu, T.; Gavazzi, R.; Marshall, P. J.; Auger, M. W.; Suyu, S. H.; Koopmans, L. V. E.; Bolton, A. S.
"Evidence for Dark Matter Contraction and a Salpeter Initial Mass Function in a Massive Early-type Galaxy"
2012, The Astrophysical Journal, 752, 163

Sonnenfeld, A.; Bertin, G.; Lombardi, M.
Direct measurement of the magnification produced by galaxy clusters as gravitational lenses
2011, Astronomy & Astrophysics, 532, 37